The present invention relates to a window lifter, a controlling device of a window lifter, and a method for the control of a window lifter.
The control and regulation of the regulating motion of a translational adjustable component, especially a window lifter in motor vehicles, is known from DE 197 45 597 A1. An efficient protection against crushing, taking into considering a sufficient adjustment force in restriction areas and forces affecting the vehicle body and further conditioned by external forces, is guaranteed according to the above known method. The method is facilitated via a regulating device, a driving device and controlling electronics. The driving device produces a regulating force which equals the total necessary force for the adjustment of the component and is further a superfluous force whereby the sum is smaller or equal to a permitted crush force. The adjustment force or the superfluous force is regulated in dependence from forces affecting the body of the vehicle or from pieces of the vehicle body.
The solution, afforded the above method, guarantees a crush protection beyond the entire adjustment area, the protection further fulfilling very high safety requirements. Additionally, it is assured that the regulating force is also sufficient in restriction areas and that a regulating device adjusts a translational adjustable component gently on the material while considering the externally affecting influences on the vehicle body which may arise from vehicle operator influence. The forces affecting the vehicle body or the acceleration forces are hereby understood as external forces which are not immediately caused by the regulating device or by a driving device, but which for example occur because of the bad condition of a road (driving over a hole) or at closing the vehicle door.
The regulation of the adjustment force or the superfluous force occurs preferably in dependence from the moving direction of the translational adjustable component and from the acceleration forces occurring in the predominant direction of affect in such a way that the adjustment force is always smaller or equal to the permitted crush force. If an acceleration force affects the vehicle body and supports the closing motion of a translational adjustable component, the threshold is preferably decreased. In the event of an acceleration force directed against the closing motion, the threshold is increased. Accordingly, the adjusting force is always sufficient such that the closing motion is securely continued and a crush protection is guaranteed.
It is furthermore provided that at an occurrence of changing acceleration forces effecting the vehicle body within a determined time frame, a regulation of the adjustment force or the superfluous force is interrupted and a threshold is preset in such a way that the adjustment force is always smaller or equal to the permitted crushing force. The time frame may be for example 100 ms. This type of execution takes into account that the threshold does not always change within a short time frame at ever changing acceleration forces affecting the vehicle body which could lead to an impairment of the movement of the translational adjustable component. By presetting a fixed threshold, which is always smaller or equal to the permitted crush force, both a secure movement of the translatory adjustable component as well as a crush protection are guaranteed.
The acceleration forces affecting the vehicle body are preferably detected by a sensor, which may be a digital sensor. Digital signals can be further processed in control regulation electronics. For the adjustment of the regulation, one or more time-related successive signals of the sensor can be evaluated by the control and regulation electronics. The repeated evaluation of the sensor provides for the safe identification of a simultaneous occurrence of the acceleration forces caused by external influences and the forces conditional by a case of crushing.
A driving device for a motor driven vehicle is known from DE 195 17 958. For electronic window lifters, the rotation of the drive is immediately stopped at the driving device for the lifter if an obstacle is put against the movement of the window while the motor turns. The driving device serves for the opening and closing of the moveable piece (window) and can be selectively started and stopped.
An electrical power meter measures the power running through the drive in a starting compensation time, a current power changing detector determines a current power increment from the determined power at each constant time frame, and a driving controlling device delivers a first or a second control signal to the driving device, whereby the driving operation is continued with the first signal depending upon the polarity of the current power increment. The drive is immediately stopped with the second signal of the drive.
Two selection switches mark the direction of the drive, a pair of push-buttons for the respective driving directions and two self-changing switches for the two directions of the drive enable a rotation of the motor via actuating one of the push-buttons.